Field of Endeavor
The present application relates to detecting isotopologues of carbon dioxide in the atmosphere and more particularly to detecting isotopologues of carbon dioxide in the atmosphere in concomitance of water or methane in a flux site.
State of Technology
This section provides background information related to the present disclosure which is not necessarily prior art.
The flux community had its beginnings in the Harvard Forest. At its founding in 1907, the original purpose of the Harvard Forest was to serve as: a field laboratory for students, a research center in forestry and related disciplines, including soils, wildlife biology, geography and botany, and a demonstration of practical sustained forestry. In 1914, Forestry education was shifted to Petersham, and the Harvard Forest was made a graduate school. The Harvard Forest mission was reprioritized in 1915 to include serving as an example to the local community for the care and marketing of forests. In 1932, the Harvard Forest was placed within Harvard's Faculty of Arts and Sciences and Graduate School of Arts and Sciences, where it has remained since.
In 2012, the U.S. Department of Energy (DOE) established the AmeriFlux Management Project (AMP) at Lawrence Berkeley National Laboratory (LBNL) to support the broad AmeriFlux community and the AmeriFlux sites. AmeriFlux is now one of the DOE Office of Biological and Environmental Research's (BER) best-known and most highly regarded brands in climate and ecological research. AmeriFlux datasets, and the understanding derived from them, provide crucial linkages between terrestrial ecosystem processes and climate-relevant responses at landscape, regional, and continental scales.
The AmeriFlux network started with a group of ad hoc flux towers already operating in such locales as Harvard Forest in Massachusetts, Walker Branch Watershed in Tennessee, Howland Forest in Maine, and at the Camp Sherman site in Oregon. By 1999 new towers were established at Duke Forest loblolly pine plantation and deciduous forest in North Carolina, on the Wind River Crane in Washington, at Morgan Monroe State deciduous forest in Indiana, on Niwot Ridge in subalpine forest of Colorado, near Douglas Lake at the University of Michigan Biological Station, at agricultural sites in Oklahoma and Illinois, over a slash pine plantation in Florida, a grassland near Fort Peck, Mont., at a chaparral in southern California, and at a ponderosa pine plantation in northern California.
The flux community currently relies on commercially available infrared gas analyzer (IRGA) units to measure CO2 and H2O concentrations (e.g., [CO2]). In conjunction with sonic anemometers, CO2 and H2O fluxes are also calculated with a technique called eddy covariance. The IRGAs measure [CO2] and [H2O] with a precision of approximately 0.15 μmol mol−1 and 0.006 mmol mol−1, respectively, at sampling frequencies of up to 50 Hz and consume up to 30 W of power, costing at least $20K for one basic unit. As such, most sites measure fluxes at only one location, usually above the canopy, and very few sites measure ecosystem-relevant isotopes of carbon and oxygen. Recent technological advances have shown that measurements of multiple CO2 isotopologues (12C16O2, 13C16O2, 18O12C16O) have the potential to reveal key information about the partitioned (photosynthesis and respiration) fluxes. Originally, samples had to be collected in flasks and transported to a facility with an isotope ratio mass spectrometer (IRMS) for analysis. In the past decade, advances have made it possible to measure in situ but still require an air-conditioned shed and large amounts of power. Sampling frequency is on the order of 10 minutes or more, and instruments cost nearly $100K according to recent quotes received from the leading suppliers of isotope measurement instruments.